Historically, dairy calves have been weaned at an early age to permit sale of the milk produced by the cow. Typically the calf will be weaned from nursing at between three and five days of age. In the past, such weaning has been a matter of converting the calf to a liquid milk diet ingested, for example, from a bucket or other container. At about three weeks of age the calf is then weaned from the liquid diet and converted to a solid diet of grain, hay and pelleted feeds. At the time of weaning the calf from the liquid milk diet to the dry grain, hay and pelleted feed, the calf sustains a shock that sets back its growth pattern for several weeks. It is not uncommon for a calf to lose significant weight during this period. Although the reasons for this period of shock may not be completely understood, it is our belief that it has to do with the development of the four compartmented stomach of the calf. The four compartments include the rumen, the omasum, the recticulum and the abomasum. In the newborn calf, milk travels down the esophagus through the esophageal groove into the abomasum. At later stages of development once the calf is on solid food the abomasum shrinks in size until it is a little more than a portion of the intestine. On the other hand, the newborn calf has a relatively small rumen stomach which at a later time becomes the primary stomach. It is our belief that the development of the rumen takes place after weaning.